Republicans appear to be getting closer to picking up the U.S. Senate seat in Nebraska even as liberal super PAC End the Gridlock spends more than$534,000 opposing the GOP candidate, state Sen. Deb Fischer.

Fischer faces former U.S. Sen. Bob Kerrey in the race to replace retiring Democratic Sen. Ben Nelson in the Republican-leaning state.

End the Gridlock was established in April in Washington, D.C., and has spent entirely in opposition to Fischer. Nonetheless, End the Gridlock’s website says it plans to focus on “high-impact races” and names only Nebraska as such a race.

Its most recent quarterly filing shows the super PAC took in $229,000 through the end of June. The top donor, Hollywood producer Sidney Kimmel, gave $100,000. Kimmel earned his fortune as founder of the Jones Apparel Group, known for such brands as Jones New York and 9 West. More recent disclosures by the super PAC Majority PAC, whose goal is helping Democrats maintain control of the U.S. Senate, show transfers to End the Gridlock totaling more than $257,000 as well.

The only Nebraska-based donor currently on record is Richard Holland, who helped build one of Omaha’s largest ad agencies. As of the end of June, he contributed $25,000 to the super PAC.

Fischer’s victory over state Attorney General Jon Bruning and state Treasurer Don Stenberg in the Republican primary came as a surprise. The Republican establishment spent hundreds of thousands backing Bruning, and conservative super PACs spent more than $1 million backing Stenberg, according to the Center for Responsive Politics.

Fischer got a late endorsement from former Alaska Gov. Sarah Palin and triumphed thanks to 11th-hour support from a super PAC funded by TD Ameritrade founder Joe Ricketts.

The New York Timesrates the Nebraska seat a “likely, though not surefire” pickup for the GOP, though it increasingly looks more certain. Fischer has a wide lead in the polls, as Kerrey has been criticized for spending the last 10 years in New York, where he served as the president of The New School.

In other outside spending news:

The super PAC National Association of Realtors Congressional Fund reported spending more than$1.3 million supporting one Democratic and three Republican U.S. representatives.

SEIU COPE, the political action committee of the Service Employees International Union, released an ad that accuses former Wisconsin Gov. Tommy Thompson, the Republican candidate for U.S. Senate, of “looking out for special interests.”

Club for Growth Action, a conservative super PAC, launched “Know,” which opposes former U.S. Surgeon General Richard Carmona, the Democratic candidate for U.S. Senate in Arizona, and “Jobs,” opposing Rep. Joe Donnelly, D-Ind., who is running for U.S. Senate.

The Now or Never PAC, a conservative super PAC, reported spending $405,000 opposing Tammy Duckworth, the Democratic candidate for U.S. House in Illinois’ 8th District.

AFSCME PEOPLE, the political action committee of the American Federation of State, County and Municipal Employees, released “Against Us” opposing Indiana State Treasurer Richard Mourdock, the Republican candidate for U.S. Senate in the state.

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About the author

Rachael Marcus is a reporter with the Center for Public Integrity, a non-profit, non-partisan independent investigative news outlet, which contributes campaign finance coverage to Marketplace. For more of their reporting on money and politics go to publicintegrity.org.